AASHTO Bridge Meeting

T-19 Software and Technology Committee

April 20, 2015 – Saratoga Springs, NY

Presenter:

Stephanie Winkelhake, PE

NYSDOT, Office of Structures

3D Bridge Design at NYSDOT The State of the Practice

Objectives

• Brief overview of how Model Driven Bridge Design got started at NYSDOT.

• Present the basic elements of the Model Driven Bridge Design method.

• Present the basic elements of the Bridge Model Management.

Bentley SELECT series 2

MicroStation V8i

InRoads V8i

ProjectWise V8i

Milestones in 3D Development in NY

• 3D CADD models of substructures were first utilized for production work in 2003

• Early adopters had their own methods to create, manage and utilize models.

• The first standards for using 3D CADD models was added to the Bridge Manual in 2008.

• Model Driven Bridge Design became a requirement for all new and replacement bridge projects in 2010.

Bridge Design Models 101

CADD Design models (sometimes call Feature Models) are graphics that represent bridge components or other design elements. Design models are always…

- True-scale and geospatial.

- The single source of critical geometric data that supplies bridge geometry to downstream tasks and work groups.

Bridge Models as Graphic Features • Models are graphic elements, or features in the

CADD file, such as solids, shapes or lines.

• Feature models are non-data based

• Data based models such as .DTM

or .ALG files used in highway

design are compatible but

inconsistent with feature models

used for bridge design.

Model Driven Bridge Design

• Site features, existing structures and proposed highway design are modeled during site data collection.

• A simple model for proposed bridge work is created during Preliminary Bridge Design.

• Refinement of geometric design is done by viewing/evaluating models concurrently.

• As the design concept evolves through Preliminary and into Final Design, the models are frequently revised to reflect the progression in design.

Model Driven Bridge Design

• During design, the aggregate of design models represent designer intent regarding bridge geometry.

• Design models are not integrated with or used for structural design.

• Design models are used for geometry dependant design and detailing tasks.

Model Driven Bridge Design

• Develop Contract Plans directly form models

• Quantity Estimating by design model measurement.

• Precisely Communicate within the design team

Model Driven Bridge Design

• Determine geometric requirements of bridge elements.

• Verify compatibility with highway design and site features.

By referencing several design models into a work file, designers can view different elements of the project’s design concurrently. This enable designer to…

• Visualize alternatives.

• Perform conflict detection.

Contractors are provided all electronic engineering data residing in the Projectwise job folder as supplemental information. Many Contractors are now using this information to facilitate construction.

Transfer to Construction

“2D or not 2D - that is the question”

• NYSDOT requires that substructures for all new and replacement bridge projects be modeled in 3D. For all other elements this decision is left to the designer.

• It is recommended that elements that are detailed in section and paid for by volume be modeled in 3D.

• Earthwork items are always detailed in section and are largely paid for by volume. Therefore, bridge earthwork item should be modeled in 3D.

2D Bridge Models • Joints

• Barrier

• Slabs

• Beams

• Diaphragms

• Bearings

• Scuppers

• Railing

• Curbs

• Lighting

• Slope Protection/ Channel Lining

• Bar reinforcement

3D Bridge Models

• All Substructures.

• Earth structures such as MSES and GRES walls.

• Structure backfills such as under drain filter and Select Structure Fill.

3D Bridge Models • Excavations for both proposed structures and excavations

needed for the removal of existing structures. Solids vs. Surfaces – both have advantages and disadvantages.

• Excavation protection such as steel sheet piling, soldier pile and lagging, or soil nailed wall.

MicroStation Model Space All design models are stored in a named “Model Space”. A Model Space is a sub-file within a MicroStation file used to compartmentalize the file. This has the benefit of allowing the designer to customize Naming of the project models

Bridge Model Management • Bridge Model Management is the statewide standard

practice for organizing, storing, sharing and using CADD work for all NYSDOT bridge projects.

• Developed to facilitate Model Driven Bridge Design.

• Documented in NYSDOT Bridge Manual.

• Requires some training.

CADD File Types

1. Bridge Design File

2. Bridge Front File

3. Personal Work files

4. Bridge Drawing files

5. Bridge Estimate File

All CADD files for Bridge Work is grouped into 5 types

Bridge Design File

Contains all modeled, location-critical components of the bridge design for which the bridge designer is principally responsible.

Bridge Design File Model Space List

The Review Model, named “[ ] REVIEW”, is an empty model

space with all the bridge design models referenced to it.

Bridge Front File

Contains all graphical information that is not the result of the bridge design effort or is not at the correct coordinates.

Most models spaces are created early on in design because most of the needed information comes from the Site Data Package. This “up-front” work can then be referenced into other files as needed later.

Bridge Front File Model Space List

Personal Work Files

Contains designers project related work. These files can be used for anything. But are never part of the finalized work

Personal Work File Model Space List

Models spaces can be used to develop ideas, check for conflicts, store alternatives not selected, cutting cross sections, creating surfaces or developing alignments.

Contains a single drawing to be included in the contract documents. References the appropriate individual models from the Bridge Design File and The Bridge Front File to show proposed bridge work.

Bridge Drawing Files

Drawing File - Model Space List

Models from the Bridge Design File and the Bridge Front File are referenced into the Plot model space. In some cases it is necessary to move or scale these reference files to efficiently layout the drawing.

Bridge Estimate File

Contains empty model spaces with references to the

design models needed to estimate the item. This

provides a single centralized location for all quantity

estimates done using Bridge Model Measurement

Quantity estimates are obtained directly by measuring the design models used to produce the contract plans.

Estimate File - Model Space List